Your iPhone, iPad, and iPod touch come with some handy apps built in, and you've no doubt added a few -- or a few dozen -- more. A good utility can elevate your device from great to greater, adding all kinds of insanely useful features that it didn't have before. But with more than half a million apps in the App Store, finding the right utilities to purchase can be a chore and a half. We've rounded up 10 of our favorites, some a little more obvious but still essential, and some that we feel are chronically overlooked.

Halfbrick has a knack for creating cheap, quick-hit apps that immediately devour any remaining free time you thought you had -- see Fruit Ninja, above all -- and new universal app Jetpack Joyride may be its finest work to date. Like precursor Monster Dash, Jetpack Joyride thrusts everyman-turned-badass Barry Steakfries in a frantic side-scrolling adventure, but as indicated in the title (originally Machine Gun Jetpack), you're no longer stuck on the ground.

Spy Mouse has been on the horizon for some time due to the pedigree of creator Firemint, who developed previous iOS smash hits Real Racing and Flight Control. And as expected, this rodent romp takes after the latter favorite by translating its familiar line-drawing mechanic to a stealth-based, cheese-snatching adventure. It works right out of the gate and holds up pretty well across the sizable campaign, plus Spy Mouse's sleek production values are right up there with the best seen on iPhone to date.

Nik Software is giving away its powerful photo app Snapseed for free, but only for two more days. The promotion, part of Apple’s 72hr App Store on Facebook free app program, started yesterday at 12 noon (PST) and will run through 12 noon (PST) on Friday.

Snapseed, which usually sells for $4.99, is a photo editing, enhancing, and sharing app, full of a lot of robust features. It is designed for the everyday user and includes the ability to take photos, enhance them with slick effects, and show them to the world through a broad range of sharing options.

Your iOS device is a crowded place. You've got an app for that and an app for that and an app for that. Wouldn't it be nice if you had at least one app that did more than just one thing? Well, you're in luck, because at least two developers have sweet little apps just packed to bursting with all kinds of function flavors.

If you regularly run interval workouts, chances are good you’ve already got a Timex or Garmin wrist watch that’ll not only remind you to change pace but also monitor your heart rate, the distances you cover via GPS, and a host of other relevant bells and whistles.

But for people who are only just discovering the joys (and pains) of interval training, the Runners Interval Timer app, priced at just $1.99, is an awesome alternative to the aforementioned gizmos, which typically run between $50 and $350.

We know you're ready for some football -- that's not even the question we want answered. The real question here: are your iOS devices ready for some football? And if not, why the heck not? We love football, you love football -- don't you think your iPad and iPhone should love it too? Well, they will once we get through with you.

Groove Coaster is a rhythm game boiled down to its essence. Where Guitar Hero had multiple buttons and Rez married its interactive soundtrack to hardcore shooting mechanics, Groove Coaster is concerned entirely with keeping a beat using its simple one-touch controls to its advantage.

Ever wonder what goes on inside your washing machine when the lid is closed? A new platform puzzle game from D7 Studios is poised to answer this age old question as the heroic stuffed animal Teddy bounces and tumbles his way through more than 90 unique levels of action.

Zombie Gunship may be the first zombie-themed game where I'm not entirely sure the enemies are undead. Ostensibly they are, but that might be what the game wants you to think. Strapped to the gunner seat of an airplane flying over a survivor's bunker, you're tasked with murdering hordes of zombies while trying your best to avoid innocent casualties.